Automatic Time Zone Correction for Handsets

T-Mobile Hungary says that it has launched a service which will continuously update the time and date in customers handsets - through the network of the mobile operator. With mobile phones spreading, less and less people wear wristwatches as the clock and calendar of cellular telephones is easily accessible, at any time.

In the future, holders of enabled telephones using the T-Mobile network in Hungary will be guaranteed to have the accurate time on their displays. Mobile networks - assuming that customers grant permission through their mobile terminals - can continuously update both the phone's clock and calendar.

T-Mobile's new network display and accurate time function (NITZ: Network Identity and Time Zone) enables updating the date and accurate time, besides displaying the operator name (T-Mobile H). The service is available across Hungary within the whole T-Mobile network (be it either GSM or 3G/HSDPA). The service can be used with NITZ enabled terminals; all the customer needs to do is activate the automatic date/time update option. Obviously activation methods vary by terminals.

Reliable background, guaranteed accuracy is inevitable for synchronisation. For this reason the clocks of all T-Mobile's switches are checked automatically every day. Clocks are synchronised using the most sophisticated tools: 2 PPS based time servers, their accuracy relative to GPS clock signals - with a variance of 1 second every 10 thousand years - is considered almost perfect.

In the course of NITZ updating three components are used to set the accurate time: firstly Greenwich Mean Time (GMT), secondly the time zone and finally the appropriate summer/winter time. The recently introduced service may also be a useful option to automatically update the clock in the mobile phones of foreign visitors, who choose the T-Mobile network upon their arrival in Hungary."

Posted to the site on 16th October 2006